Electrical connector clamp



@Y 2y w50 T. BIRKENMAIER ELECTRICAL CONNECTOR CLAMP Filed March l2, 1947 FIG. I.

Patented May 2, 1950 ELECTRICAL CONNECTOR CLAMP Theodore Brkenmaier, St. Louis, Mo., assigner to W. N. Matthews Corporation, St. Louis, Mo.,

a corporation of Missouri Application March 12, 19427,` Serial No. 734,098

3 Claims. (Cl. 173-273) This invention relates to electrical connector clamps and, more particularly, to clamp devices of this class for electrically connecting a tap-off wire to a line wire.

Among the several objects of the invention may be noted the provision of an electrical connector embodying an improved clamp for readily effecting electrical connection between a tap-off wire and a line wire; the provision of a connector ofthe class described adapted easily to be applied and rmly attached to a line Wire by means of the usual clamp stick; the provision of a connector of this class adapted to remain securely clamped in electrical conductive relation to the line wire despite vibration or other factors tending to loosen the clamp, yet which is easily removed from the line wire when so desired; and the provision of a connector such as described which is easy and economical to manufacture. Other objects will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of the application of which will be indicated in the following claims.

ln the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

Fig. l is a side elevation of the electrical connector of this invention;

Fig. 2 is an end elevation thereof as viewed from the right of Fig. 1; and,

Fig. '3 is a view similar to Fig. 1, but partly in section and `illustrating `the clamp applied to a line wire.

Similar reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to the drawing, there is generally shown at I a clamp body comprising a web portion 3 and a ange 5. The clamp body is provided with a jaw 'l formed with a recess 9 shaped to accommodate a line Wire A (Fig. 3). The web 3 of the clamp body carries wire-connector means l I of any suitable construction for attaching a tap-oil wire B thereto. As illustrated herein, means Il comprises a split bolt I3 carried by the web 3 and having a nut I5 threaded thereon adapted to be screwed up on the bolt to clamp the tap-off wire in electrical conductive relation to the web.

Spaced wall anges I1 and I9 extend outward ifrom the end of the clamp body opposite the jaw 'I generally at right angles to the nange 5. The outer ends of anges I1 and I9 are preferably, though not necessarily. joined by a web 2| to strengthen the construction. A lock nut 23, of a special construction tobe described, is nonrotatably received in therecess or compartment 25 between flanges I'I and I9. This lock nut is threaded on a clamp bolt 2l, the latter extending freely through unthreaded apertures 29 and 3I in 'flangesor buttresses `I'I and I9.

The clamp bolt2l, on Aits upperV end adjacent jaw l, carries a jaw 33 cooperating with jaw 'I for clamping the line Wire A` therebetween. Jaw 33 is formed with a recess 35 shaped to accommodatethe line wireA.` The upper end of the bolt 21 is rotatableun` the jaw 33` but is xed againstaxial movementwith respect thereto by means of apinf3l fixed in the jaw and traversing groove 39linthe end ofthe bolt. The jaw 33 `is prevented from rotation by engagement of thesidedl thereof 'with flange 5 of the clamp body, and also by engagement of ears #13 thereon with theedges of 'ange 5. Ears 43 also cooper-,

ate with theedges of flange 5 to guide the jaw 33 in its movement toward and away from jaw The lower fend of the bolt is formed as an eye 45to receive ahook on the end of a clamp stick for turning the bolt.

The lock nut 23 comprisesa generally rectangular nut, preferablyformed of a lubricantbearing metal, such as an oil-bearing compressed powdered and sintered metal. This nut is transversely slitted. as indicated at 41, to provide two transverse tongues "49connected by a base portion 5I.` Rotationof the nut is prevented by engagement of a flat side thereof either with flange 5 ofthe `clamp body `'orw'ith web 2l. Flanges Il and I9 function as stops to limit axial movement of the nut.

The inside surface" 53 of thelower iiange I9 (itss'urface within the nutreceiving recess 25) is inclinedwith respect to" thenormal plane of the lower surface ofthe nut, as illustrated in Fig. 1. The nut" is received in rfe`cess"`25 with thetongues 49 extendingv toward the highside of this inclined surface'. While as illustrated herein, the tongues extend outward fromltheliange5 and the surface 53 inclines upw'arda'vvayfrom flange I9, it will be apparent that this relation may be reversed. It will also be apparent that the tongues may extend parallel to the ilange, instead of transversely with respect thereto, ln which case the surface 53 will again be inclined upward toward the free end of the tongues. It will be further apparent that the inside surface of the i'iange i9 could be perpendicular to the ange 5 and the lower surface of the nut 23 may be inclined. Other alternatives will readily suggest themselves.

The web 3 of the clamp body has an aperture 55 therein for receiving the hook of a clamp stick. In employing the clamp of this invention to make a connection between the tap-olf. wire and a line wire, the procedure is asfollows:

The clamp bolt 2l' is turned to retract jaw 33 until it is spaced a suicient distance from jaw l to permit the clamp to be applied over alineV wire A. The tap-oil` wire B is clamped tothe clamp body l by the means il.

engage jaw l over the line wire. of the hook of the clamp stick from aperture 55,

the clamp is suspended on the 1ine wire A, recess,

9 in jaw accommodating the line wire.

The hook of thel clamp'stick is then inserted in the eye i5 of the bolt and manipulated to turn the bolt to movejaw 33 toward. jaw i so as to clamp the wire between these jaws. During this operation, the bolt turns-easily in the nut 23. Rotation of the nut is prevented by means of engagement of a fiat side thereof either with flange 5 or strut 2.l,rso=that turning of thebolt effects axial movement of thebolt.

When the bolt has beenturned sumciently to cause jaw 33 to exert clamping-force on the line wire A, as illustrated in Fig; 3, further upward axial movement of thebolt isprevented. Further turningof the bolt, while it doesnot result in axial movement of the boltycauses thenut 23 to travel downward into pressure engagement with the inclined thrust surface 53'. This distorts the nut, causingk the. lowerY tongue e9 to become cantedV toward the. upper tongue, as illustra-ted in Fig.V 3. Some looseness in the threads favors distortion. This causes the threads of the nut to bind onv the bolt threads,l thereby releasably to lock the nutto the bolt to maintain the Yline Wire A tightly clamped. between the jaws l and 33 despite. vibration or. other factors whichtendto loosen-the nut.

The clamp may be readily.:removedfromv the linewire A, if soV desired, byf turning thefbolt. with the clamp stick.to:retract jaw 33; While considerable force must be initially exerted toV turn thebolt to unlockl nut: 2.3,the': amount of' force required isvnotv unreasonable. When the bolt is initially turned, `thenut .23ftravels upwardr away from engagement Vwith the inclined thrust surface 53 and tonguesd return to their normal parallel relation illustratedinFig. 1, due tothe resilience ofthe portionsof the nut connecting its base portion 5iv and the tongues, After thc nut has been thus unlocked, the bolt may be; turned easily becausethe, induced distortion is not beyond the elastic limit. The nut is preferably made of'. the aforesaidlubricant-bearingV Letal. which provides for convenient constant lubrication of thethreadsv so that the bolt may be turned in the nut withoutv requiring unrean sonable force, even after the clamp has been applied toa line wiregin an exposedlocation for. a considerable period of time.-A

Thehook of aclamp stick (not shown) islinsertedin.aperture 55 and the stick employed to raise the clamp and Upon removal Gil In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing4 shall bel interpreted as illustrative and notxin-.-.a-limitinglsense,

I claim:

- 1. An electrical connector comprising a clamp body having a jaw thereon and an aperture therein adapted to receive the hook of a clamp stick, means for. attaching a tap-off wire to the clampbody, a boltmounted for axial movement in a pairof spacedflanges which extend outward from the clamp body, said bolt carrying at one endeJ jaw cooperable with the jaw on the clamp body for clamping a line wire therebetween, the other end of the bolt being formed as an eye to receive theA hookof a` clamp stick, a-,nut nonrotatably mounted inthe recess between said,

flanges butA adapted for limited. axialy movement therein, said nut being threaded on` said bolt, said nut being transverselyA slit to form two spaced tongues, the inner surface of the flangeY remote from the jaw-carrying end` of said bolt being inclined to the adjacent surface of the end of the nut whenthelboltA is retracted to separate said jaws.v Y

2. An electrical connector as set forth in claim l, wherein the nut isr formed of a lubricante bearing material.

3. in electricalconnectorr comprising a` clamp body having afjawa tap-off.\vire.connector carried by the clamp body, af boltlcarriedv byl the clampbody for rotation and-for axial movementv toward and. away from the jaw on the clamp body, a jaw rotaryon the end of the bolt opposed to the jaw on the clamp body for clamping a;

line wire therebetween whenthel bolt is moved toward'theY jaw on4 the clamp bodyrsaid jawon the bolt having. sliding, non-rotary engagement with the clamp body, a nut. formed of lubri-` f, cantfbearing material having a. transverseslotr toform two spaced tongues threaded onthe bolt and located between-the jaw on-the bolt and the other end of: the bolt, said, clamp body being formed .with portions engageable-with the nut for` preventing rotation thereof and for limiting axial movement thereof Vandadapted to cause one of the tongues to cant toward the.- other when thebolt. isturned to,v clamp a line-wire-between the THEODORE BIRKNMAIER.

REFERENCES CITED r)The following references: are; ofrecordainpthefile of this patent:

UNITED STATES PATENTS' Number NameV Date Re. 20,915l Bergstrom. Nov. 15, 1938. 2,253,432 Johnsonn Aug, 19, 1941Y 2,266,968 Hamilton Dec. 23, 1941.. 2,319,602 Hendley May, 18, 1941A 

